The first telephone numbers in Arkansas with the 327 area code will be assigned to new customers as early as May 2013, according to Neustar Inc., a Virginia-based firm that administers the nation’s phone numbering system.

The 327 area code will be assigned when numbers for the 870 area code are exhausted. In April 2012, a customer education program about the changes will commence, the Arkansas Public Service Commission said. In October 2012, customers in the 870 area code will be allowed to dial local calls with either seven digits or 10 digits including 870.

In April...